Index: uspace/lib/usbdev/src/devdrv.c
===================================================================
--- uspace/lib/usbdev/src/devdrv.c	(revision 3875af6590a4482f2b057fc9df39681c9545f726)
+++ uspace/lib/usbdev/src/devdrv.c	(revision 5917859cf6cc8bfe7b9390ef0eaa2deffdc14377)
@@ -333,6 +333,7 @@
 	int rc;
 
-	size_t pipe_count = count_other_pipes(endpoints);
+	const size_t pipe_count = count_other_pipes(endpoints);
 	if (pipe_count == 0) {
+		*pipes_count_ptr = pipe_count;
 		*pipes_ptr = NULL;
 		return EOK;
@@ -445,10 +446,10 @@
 {
 	assert(dev != NULL);
-	assert(((pipes != NULL) && (pipes_count > 0))
-	    || ((pipes == NULL) && (pipes_count == 0)));
 
 	if (pipes_count == 0) {
+		assert(pipes == NULL);
 		return EOK;
 	}
+	assert(pipes != NULL);
 
 	int rc;